Using Some Technical Operations For Improvement of Quality of King Ruby Grapes

Document Type : Original Article

Abstract

THIS investigation was conducted for two successive seasons (2014 & 2015) on King Ruby cultivar in a private vineyard at El-deer village, Aga Center, Dakahlia Governorate, Egypt. The chosen vines were fifteen years old, planted in a clay soil under surface irrigation system, spaced at 2 x 3 m using spur pruning under bilateral cardon trellis method with supporting by double T system. This study was carried out to disclose the effect of manual thinning either removing one quarter of the clusters or removing the terminal quarter of the cluster solely after fruit set or in combination with leaf basal removal after fruit set or with trunk girdling at veraison stage.
The results showed that all conducted treatments were effective in improvement the quality of King Ruby grapes as compared with control. Although the vines for which the terminal quarter of the clusters is removed alone or in combination with leaf basal removal or girdling or with leaf basal removal and girdling decreased cluster weight as compared with the vines for which one quarter of the clusters is removed alone or in combination with leaf basal removal or girdling or with leaf basal removal and girdling but gave the highest yield and improved physical and chemical properties of berries such as berry weight, volume, length and width as well as SSC, SSC/acid ratio, total anthocyanin, total sugar, decreased total acidity in berry juice and decreased the percentage of shot berries /cluster.
The application of removing the terminal quarter of the clusters after fruit set in combination with leaf basal removal after fruit set and girdling at verasion stage gave the best values in yield and improved physical and chemical characteristics of berries.

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